Hi gar\yeohchux,
Thank you for contacting Intel.
The operating temperature of Intel® Ethernet QSFP+ Optics is 0 to 70°C. However, there's no operating temperature for cable since it doesn't have operating components in it.
Please refer to Product Briefs on the links below:
1. Intel® Ethernet QSFP+ Optics
2. Intel® Ethernet QSFP+ Cables
Please let us know if you have other inquiries.
Sincerely,
Sandy